1. Field of the Invention
The present invention relates to a method of manufacturing a magnetic head. In particular, the present invention relates to a method of manufacturing a magnetic head suitable for attaching a slider to a suspension with good accuracy.
2. Related Background Art
Hard disk drives (hereinafter called HDDs) are increasing in capacity and being made thinner. Together with these advances, magnetic heads (20%, 30% sliders) are also being made smaller.
When bonding a slider, on which a giant magneto-resistive (GMR) element is formed, to a suspension side with conventional processes of manufacturing magnetic heads, positioning of the slider is performed first using the external shape of the slider as a reference. An adhesive agent is applied to a rear surface side of the slider (side opposite to a side where an air bearing surface (ABS) is formed) after positioning the slider, and the slider side is made to contact a distal end of the suspension, which has been positioned by using a tooling hole. The slider side and the distal end of the suspension are bonded through the adhesive.
Methods are also known in which slider positioning is performed without using the external shape of the slider. In one method, a physical positioning portion is provided on the slider, and positioning of the slider to the suspension side is performed by using the positing portion (refer to JP 4-17174 A, for example). In another method, a concave portion that corresponds to the external shape of the slider is provided at the distal end of the suspension, and positioning of the slider is performed by using the concave portion (refer to JP 10-293981 A, for example).
Furthermore, there are also known a method in which a through hole is formed in the slider, and assembly is performed taking the through hole as a positioning reference (refer to JP 2000-123515 A, for example), and a method in which positioning of the slider with respect to the suspension is performed by taking an inner side surface of a rail fabrication portion of the slider as a reference (refer to JP 6-150597 A, for example).
However, problems like those described below exist with the conventional magnetic head manufacturing methods described above.
Namely, it is very important to attach the suspension by taking the ABS formed on the slider as a reference in order to stabilize the flying attitude and the electrical characteristics of the magnetic head across inner and outer circumferences of a disk.
The ABS in the slider is generally fabricated by ion milling, while the external shape of the slider is fabricated by machining, thus forming the ABS and the external shape of the slider through independent processes.
However, positioning between the slider and the suspension is conventionally performed with the external shape of the slider used as a reference, as described above, and the attachment position of the suspension thus does not always coincide with the position found when taking the ABS as a reference, and the fabrication processes differ for the ABS and the external shape of the slider as described above. Consequently, when an inner side surface of the rail fabrication portion of the slider is taken as a reference, the center of the inner side surface may not coincide with the center of the ABS. The designed flying attitude and electrical characteristics may thus not be obtainable.
Accompanying miniaturization of sliders and more complex ABS patterns (in order to stabilize flying characteristics), it is expected that accurately attaching the suspension by taking the external shape of the slider as a reference will become increasingly difficult.
Furthermore, there is a fear that a balance between positive pressure and negative pressure in the ABS will go out of balance, making it impossible to stabilize the flying attitude of the slider, when forming through holes and the like used for positioning in the slider itself.